Coupling for metal tubing



Aug. 3Q, 1938. s GUARNASCHELLI 2,128,459

COUPLING FOR METAL TUBING y Filed April 29, 1936 l' /4/ .f W 2/ y H1240 m ATTO R YS Patented 1938 Nirso As'm'rl-zs vCOUPLING FOR METAL TUBING i Stephen Guarnaschelli, Brooklyn, N. Y., assigner to Packless Metal Products Corporation, lNew York, N. Y., a corporation of Delaware Application April 29, 1936, Serial No. 76,931

` 1 Claim.

This invention relates to a coupling for metal tubing and its object is to provide a simple and Further objects of the invention will appear from the following specification taken in connection with the drawing which forms a part of this application.

This invention specifically is an improvement upon that disclosed in application, Ser. No. 67,624, filed by me on Mar. '7th, 1936.

' o Referring to the drawing- Fig. l is a sectional elevation of a part of a metallic tube and the parts of a coupling device which embody the. present invention.

Fig. 2 is a sectional elevation of two of the 35 parts of the improved coupling shown in Fig. l. Fig. 3 is a sectional elevation of the parts shown in Fig. l' but in different relative positions. iig. 4 is a sectional lelevation of the parts `shown in Fig'. 1, shown in their fully assembled 30 positions.

Fig. 5 is an end view of a split collar which is shown in the preceding gures.

Fig. 6 is a side elevation of a modiflcation of the collar which is shown in Fig. 5.

35 The means used for accomplishing the purpose of this invention comprises two main coupling members A and B which are arranged to be screwed together to facilitate vsuch operation with at least a part of the outer surface of each 4i `of these members so formed that it may be engaged by a wrench. According to the usual con-l struction these parts are made hexagonal.

IIldesignates a metallic tube over the end of which is a split collar Il, which as shown has an 45 inner surface as shown in Figs. 1, 3, 4 and 5, which is roughened to engage the tube I Il. A convenient way of roughening this surface is to cut a screw thread on it. as shown at I2. This collar comprises a cylindrical portion I3, the end 50 I4 of which is chamfered. The other end of it is vconstructed to form a conical surface I5 at an angle to cooperate in forming a are on the end of the tube I0. 'I'he portion I6 surrounding this cone is also conical, but at a flatter angle which 55 is arranged to perform a function which will (ci. zas-124) appear hereinafter. 2t is a ring, the outer surface of which as shown is cylindrical and threaded. 'Ihis ring has an internal bore 2| into which the cylindrical part Il of collar II is adapted to be forced. It also has a conical ln- I terna] surface 22 which is inclinedto cooperate with the surface I6 of the collar II.

'I'he coupling member B is threaded as at I0. Beyond this threaded portion is is constructed with a cylindrical chamber 3| to receive the ring 10 20. The ring is adapted to be screwed through the threaded portion of couplingv member B as shown inl Fig. 2. The chamber 3| is larger in all of its dimensions than the ring 2li so that the latter is contained loosely within this 15 chamber.

The other coupling member A has an internal bore slightly less than that of ihe tube Ill and its inner end 4B is conical and formed at the same angle as that of the'pa'rt I5 of the collar II. The 20 cylindrical portion I3 of collar II is made of substantially the same diameter as that of the part 2| of ring 20. The internal diameter of the part I2 of the collar II is slightly less than the outside of the tube III to which it is to be applied. 25 In operation the collar I I is spread sumciently to permit it to be placed over the end of the tube III. It is then forced back on the tube to allow a portion of the tube to extend beyond it as shown in Fig. 1. is screwed into the coupling member B as shown in Fig. 3. As it advances its conical portion `Il engages the inside of the tube III and pushes it back with the collar I I on it and at the Sametime starts to flare. the outer end of the tube. As -the collar II is moved toward and into the'ring 2l. its cylindrical portion I3 will be contracted by its engagement with surface 2i of the ring 2l.

'causing its internal roughened surface I2 to grip the tube Il! tightly. As its movement into the 40 ring 20 is-completed, its surface I8 will engage the surface 22 ofthe ring with a wedge-like effect which causes these two parts to be securely gripped together as shown in Fig. 3. When in this position the coupling member B is freely rotatable about collar II, ring 20 and tube I0. It may therefore be rotated about the tube without exerting any torsional effect upon the latter.

As the coupling members A and B are relatively rotated to complete their engagement, the conical surface 40 of coupling member A will further flare an end of the tube until the parts assume the positions in which they are shown in Fig. 4. This will form a leak-proof connection between the end of the tube I0 and the coupling member 56 Then the coupling member A 30 use of any tools other than such wrenches as may be applied to the coupling members.

' Such couplings as have heretofore been made by outwardly flaring the endl of ya. tube are weakest at the base of the flare. According to the method herein described, this dic'ulty is overcome because the ared end of the tube remains of substantially the same thickness as that of the body of the tube and it moreover is reinforced at the base of the fiare by the collar ii.

The object of roughening the inside of collar li is to cause it to grip the tube I0 by deformation of the part of the outer surface of thetube which it engages in order to prevent longitudinal movement of the collar of the tubeand any desired formation of the collar may be used which accomplishes this purpose, for example, collar l iA, Fig. 6, is made with perforations il, into which a. part of the metal of the tube is extended during the operation of applying the coupling. Other mddiicatins than this may be made and other A. This is accomplished easily and without the changes in the construction and in the arrangement of the various co-operating parts may be made without departing from the spirit or scope of the invention as expressed in the following claim.

What I claim is:

Means for connecting a ductile metal pipe to a tting, said tting having a configuration adapted to enter and iiare the'end of the pipe when the pipe and iitting are forced together, means for forcing the fitting into the end of the pipe to form a. are thereon, comprising a sleeve adapted to be fixed to the pipe at a point spaced from the end thereof and having an end portion corresponding to the configuration of the end of the fitting and having a circumferential shoulder forming an abutment and a second sleeve surrounding said first named sleeve and engaging said abutment, and means engaging said second sleeve and fitting for drawing the fitting into the end of the pipe.

STEPHEN GUARNASCHELLI. 

